The Spurs have White, DeRozan, Gay and Bertans. Two of those players are on the court at all times. With the way that play Gay right now, they don't have a traditional 10-man rotation, so there isn't a direct correlation between the bench and starters. Gay is usually in for the bench units, and he and Bertans are the forwards. But then Gay leaves and DeRozan comes in, and he and Bertans continue to be the forwards. Gay is DeRozan's backup as much as Bertans is Gay's backup.
I think we all agree that SF depth would be nice. But bumping the thread after every loss as if they've been because of the lack of SF depth doesn't make sense. You mentioned in the Bulls game I think that Dunn scored because a guard was on him. How would that have not been the case had the Spurs had an SF? Dunn's a guard. A guard was going to be on him anyway.
I stand corrected that you didn't explicitly say that. But still, you put him on there as if he were forward depth, and the Spurs got him.